It is not necessary to invest with the same amount of money. It is okay to buy consistently every week or month in the DCA strategy, but there is no obligation for you to buy the same amount. You can increase the investment amount in any month/week if you want or reduce it if necessary. It completely depends on your ability. Investing in the DCA strategy means that you will invest continuously in any amount for a certain period of time depending on your ability and hold it for a long time.
In terms of the amount of money, if you have the ability to invest the same amount every week/month, then you can definitely invest without making any change in the amount. But if you have difficulty in maintaining the same amount of investment or you are unable to do so, then it is not necessary for you to maintain the investment amount. Invest as much as you can from the remaining money after meeting your daily needs. There is no problem in increasing or decreasing the amount of money as needed. However, I would advise you not to reduce your investment amount unnecessarily and not to invest more than you can afford. Invest in an amount that you feel comfortable with.
Well said, i see that people get confused when it comes to the amount of money that's to be invested in Bitcoin, the fact an investor started with a particular amount of money doesn't mean they'll continue with that exact amount of money all through their investment journey, maybe the person started small with a $100 weekly or monthly doesn't mean they should continue with that amount for 4-5 years, along the line when they generate more income they can improve that amount to something more better according to how much they begin to earn and can even change from investing on a monthly or weekly basis to daily depending on how long they can continue and if things get bad along the line, maybe their expenses becomes more pilled up, it's not a bad idea to reduce the amount or switch back to monthly intervals till things get better again, Bitcoin investment should be done according to one's financial capacity, so far the person continues to invest continuesly, overtime and not the other way round, investing more than one can afford is causing more problems to one's self like those who take loans to invest or people who fail to separate their discretionary funds from the funds meant for investment, the blame/regrets would be on them rather than Bitcoin.